pTK-Hyg is a selection vector that confers hygromycin resistance in mammalian cells for the selection of stably transformed cells. pTK-Hyg is especially useful for selection of double-stable cell lines using the Tet-On? or Tet-Off? Gene Expression Systems because the absence of an enhancer element on pTK-Hyg prevents the unwanted activation of pTRE- and pBI-derived plasmids upon cointegration into the host cell’s genome.
pTK-Hyg can be cotransfected into the host cell line with an expression plasmid that contains a gene of interest using any standard transfection technique. Most mammalian cell lines require 200 μg/ml of Hygromycin to select for stably transformed cells.